The mixing ratio for 2K paint, also known as two-pack or twin-pack acrylic, is two parts color, one part hardener and 10 percent thinner. The paint actually consists of acrylic and melamine resin, which is mixed with poly-isocyanate resin as the hardener.
It contains far less thinner than the older cellulose paint, which results in far less wastage by evaporation. Heat might be used to speed up the drying time.
2K paint is significantly harder and more resilient than cellulose paint when dry, maintaining its color despite petrol, acid rain, sunlight and other oxidizing factors. However, two-pack is generally a professional-only paint because of the toxicity of the isocyanate fumes, and the expense of necessary spray booths and breathing apparatus.